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Using Geographical Information Systems To Investigate Spatial Patterns In Fossils Of Tapirus Polkenis From The Gray Fossil Site, Washington County, Tennessee, Winn Addison Ketchum Dec 2011

Using Geographical Information Systems To Investigate Spatial Patterns In Fossils Of Tapirus Polkenis From The Gray Fossil Site, Washington County, Tennessee, Winn Addison Ketchum

Electronic Theses and Dissertations

Discovered in 2000, the Gray Fossil Site provides a snapshot of the flora and fauna that lived during late Miocene to early Pliocene time in eastern Tennessee. These fossils occur in sediments consisting of fine-grained clays and sands of lacustrine origin, which were deposited after multiple sinkholes formed in the underlying Knox Group basement carbonates. Three-dimensional nearest neighbor analysis has been applied to fossils of Tapirus polkensis, characterizing the spatial patterns exhibited. These analyses determined the importance of taphonomic and depositional processes that occurred during the sites formation. Six characteristics were analyzed, four at the bone level including carnivore …


Nitrogen Retention And Denitrification In Reservoirs, Erin Grantz Dec 2011

Nitrogen Retention And Denitrification In Reservoirs, Erin Grantz

Graduate Theses and Dissertations

Studies coupling direct measurements of micro-scale nitrogen (N) cycle processes with ecosystem-scale flux estimates are needed to determine N retention hotspots within river networks, where up to 50% of terrestrial loading to aquatic systems is retained. This study examined the role of denitrification, a microbially-mediated reactive N removal pathway, in ecosystem-scale N retention in 3 small (< 1 km2), shallow flood-control reservoirs. Annual reservoir N retention was estimated through mass balance modeling of system inputs and outputs. Annual denitrification rates were estimated by combining multiple measurements of seasonal, habitat-specific dinitrogen gas (N2) fluxes. Annual reservoir N retention ranged from 14 - 19 g m-2 in the reservoirs, while reactive N removal through denitrification was 13 - 25 g m-2. Denitrification efficiency, or the portion of the retained N load that was denitrified, was high relative to other lentic systems and was > 100% at 2 sites. Previous lentic denitrification studies may have underestimated denitrification efficiency by not considering water column denitrification, which was 50% of total denitrification at one study reservoir. However, not all potential inputs, most importantly biological N2 fixation, were included in this …


Spatial And Temporal Variations In The Air-Sea Carbon Dioxide Fluxes Of Florida Bay, Christopher Michael Dufore Nov 2011

Spatial And Temporal Variations In The Air-Sea Carbon Dioxide Fluxes Of Florida Bay, Christopher Michael Dufore

USF Tampa Graduate Theses and Dissertations

The flux of CO2 between the ocean and the atmosphere is an important measure in determining local, global, and regional, as well as short term and long term carbon budgets. In this study, air-sea CO2 fluxes measured using a floating chamber were used to examine the spatial and temporal variability of CO2 fluxes in Florida Bay. Measurements of dissolved inorganic carbon and total alkalinity obtained concurrently with chamber measurements of CO2 flux allowed calculation of ΔpCO2 from flux measurements obtained at zero wind velocity. Floating chamber measurements of ΔpCO2 were subsequently coupled with wind speed data to provide a simple …


Flow Dynamics Of An Accumulation Basin: A Case Study Of Upper Kahiltna Glacier, Mount Mckinley, Alaska, Seth Campbell, Karl Kreutz, Erich Osterberg, Steven Arcone Nov 2011

Flow Dynamics Of An Accumulation Basin: A Case Study Of Upper Kahiltna Glacier, Mount Mckinley, Alaska, Seth Campbell, Karl Kreutz, Erich Osterberg, Steven Arcone

Dartmouth Scholarship

We interpreted flow dynamics of the Kahiltna Pass Basin accumulation zone on Mount McKinley, Alaska, USA, using 40, 100 and 900 MHz ground-penetrating radar profiles and GPS surface velocity measurements. We found dipping, englacial surface-conformable strata that experienced vertical thickening as the glacier flowed westward from a steep, higher-velocity (60 m a−1) region into flat terrain associated with a 90° bend in the glacier and lower velocities (15 m a−1) to the south. Stratigraphy near the western side of the basin was surface-conformable to ∼170 m depth and thinned as flow diverged southward, down-glacier. We found complex strata beneath the …


2011 Percival Allen Medal Award, Corina Ionescu, Tudor Berza Nov 2011

2011 Percival Allen Medal Award, Corina Ionescu, Tudor Berza

Studia UBB Geologia

The Association of European Geological Societies (AEGS) connects geological societies all over Europe. In 2006, the AEGS Executive Committee established an award named for Prof. Percival Allen FRS, one of the AEGS's founders. This medal is given biennially to a geoscientist for outstanding achievements in the field of international relations in Earth Sciences. Other than a distinguished record in fostering international relations in geosciences, there are no special eligibility criteria. The Award Committee announces the laureate at the Meetings of AEGS (MAEGS).

Dr. Jens Dieter Becker-Platen from Germany (at MAEGS-15, held in Tallinn 2007) and Dr. Eduardo de Mulder from …


Magnetic Susceptibility As A Proxy For Investigating Microbially Mediated Iron Reduction, Farag M. Mewafy, Estella A. Atekwana, D. Dale Werkema, Lee D. Slater, Dimitrios Ntarlagiannis, Andre Revil, Magnus E. Skold, Geoffrey N. Delin Nov 2011

Magnetic Susceptibility As A Proxy For Investigating Microbially Mediated Iron Reduction, Farag M. Mewafy, Estella A. Atekwana, D. Dale Werkema, Lee D. Slater, Dimitrios Ntarlagiannis, Andre Revil, Magnus E. Skold, Geoffrey N. Delin

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

We investigated magnetic susceptibility (MS) variations in hydrocarbon contaminated sediments. Our objective was to determine if MS can be used as an intrinsic bioremediation indicator due to the activity of iron-reducing bacteria. A contaminated and an uncontaminated core were retrieved from a site contaminated with crude oil near Bemidji, Minnesota and subsampled for MS measurements. The contaminated core revealed enriched MS zones within the hydrocarbon smear zone, which is related to iron-reduction coupled to oxidation of hydrocarbon compounds and the vadose zone, which is coincident with a zone of methane depletion suggesting aerobic or anaerobic oxidation of methane is coupled …


Historical Vegetation Of Central Southwest Oregon, Based On Glo Survey Notes : Final Report To Usdi Bureau Of Land Management, Medford District, O. Eugene Hickman, John A. Christy Oct 2011

Historical Vegetation Of Central Southwest Oregon, Based On Glo Survey Notes : Final Report To Usdi Bureau Of Land Management, Medford District, O. Eugene Hickman, John A. Christy

Institute for Natural Resources Publications

Historical vegetation at the time of European settlement is of great interest to both the public and land managers, but is poorly documented. One source of data are the earliest land survey records of the General Land Office (GLO). Rectangular township surveys in Southwest Oregon were initiated in the mid 1850’s as settlers began to claim homesteads in the Bear Creek Valley surrounding what is now Medford. We examined GLO land survey field notes and plats (maps) accompanying the surveys, transcribed GLO landscape data into an Access database, and classified the data set into very general vegetation types for mapping. …


A Simplified Approach For Estimating Soil Carbon And Nitrogen Stocks In Semi-Arid Complex Terrain, Melvin L. Kunkel, Alejandro N. Flores, Toni J. Smith, James P. Mcnamara, Shawn G. Benner Oct 2011

A Simplified Approach For Estimating Soil Carbon And Nitrogen Stocks In Semi-Arid Complex Terrain, Melvin L. Kunkel, Alejandro N. Flores, Toni J. Smith, James P. Mcnamara, Shawn G. Benner

Geosciences Faculty Publications and Presentations

We investigated soil carbon (C) and nitrogen (N) distribution and developed a model, using readily available geospatial data, to predict that distribution across a mountainous, semi-arid, watershed in southwestern Idaho (USA). Soil core samples were collected and analyzed from 133 locations at 6 depths (n=798), revealing that aspect dramatically influences the distribution of C and N, with north-facing slopes exhibiting up to 5 times more C and N than adjacent southfacing aspects. These differences are superimposed upon an elevation (precipitation) gradient, with soil C and N contents increasing by nearly a factor of 10 from the bottom (1100 m elevation) …


Effects Of Climate Change On Spring Ecosystem Hydroecology As A Guide To Developing Alternative Water Policies, Scott Mensing, Saxon E. Sharpe, Scott Bassett, Don Sada, Jim Thomas Oct 2011

Effects Of Climate Change On Spring Ecosystem Hydroecology As A Guide To Developing Alternative Water Policies, Scott Mensing, Saxon E. Sharpe, Scott Bassett, Don Sada, Jim Thomas

Climate Change Seminar Series (NNE)

Hydroecology: the interface of ecological systems and water which combines the scientific disciplines of hydrology and ecology

Goal: evaluate the hydrologic and climate history using pollen, loss on ignition, total inorganic carbon, and invertebrates from spring sediments in Spring Valley, Eastern Nevada and Snake Valley, Western Utah


Droughtscape, Fall 2011, Kelly Smith Oct 2011

Droughtscape, Fall 2011, Kelly Smith

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

Drought Preparedness Community Options

Drought Likely to Persist, Intensify Across South

Database Will Help Planners Find Options

Impacts: Ag Losses, Fire, Water Restrictions

NDMC Welcomes International Visitors

New Drought Impact Reporter Online

Sim-Drought, Available Now at Select Agencies


Earth News, V35, Fall 2011, Department Of Earth Science, University Of Northern Iowa. Oct 2011

Earth News, V35, Fall 2011, Department Of Earth Science, University Of Northern Iowa.

Earth News

Inside this issue:

--- Faculty & Staff News
--- Emeritus News
--- Sunday at the Quarry
--- STORM 2011
--- Grant Activities in Hydrologic Sciences
--- Geology for Iowa Teachers
--- Award Recipient: Sherman Lundy
--- Award Recipient: De Anna Tibben
--- Award Recipient: Aaron Spurr
--- Student Award Recipient: Matt Even
--- Student Research Presentations
--- Internships & Seminars
--- Earth Science Graduates
--- Sigma Gamma Epsilon
--- Making a Difference
--- Alumni News
--- Gifts from Alumni & Friends


Effect Of Reworking And Bioturbation On Sedimentary Reactive Iron Within A Microtidal Estuary, Amy Kathleen Pitts Oct 2011

Effect Of Reworking And Bioturbation On Sedimentary Reactive Iron Within A Microtidal Estuary, Amy Kathleen Pitts

OES Theses and Dissertations

Mixed redox conditions in sediments due to physical reworking may allow for enhanced remineralization of refractory organic matter due to Fe(III) redox cycling. In part this may occur because easily reducible iron oxides can be used by heterotrophic bacteria to remineralize the organic carbon. This phenomena has been observed in bioturbated sediments and in areas where physical factors (such as strong bottom currents) constantly rework the sediments. To specifically determine the effects of physical reworking and bioturbation on concentrations of easily reducible iron oxides, reactive iron concentrations were measured in surface sediments taken from two contrasting sites in the York …


Quantification Of Nitrate Sources And Sinks Using A Water Quality Network In Morro Bay Estuary, California, Johanna Nadia Jean Weston Oct 2011

Quantification Of Nitrate Sources And Sinks Using A Water Quality Network In Morro Bay Estuary, California, Johanna Nadia Jean Weston

Master's Theses

Using an instrumented water quality network in Morro Bay Estuary, California from 2007 to 2010 (15 min sampling frequency), this study addressed the two objectives of constructing a nitrate budget and assessing the influence of sampling frequency on water quality parameters. These two objectives led to the submission of an original report of research (Appendix A) and a note (Appendix B) to peer-reviewed journals.

The first objective was to characterize the high spatial and temporal variation in physical parameters and nitrate concentrations and to construct a nitrate budget quantifying sources and sinks of nitrate from the ocean, streams, and groundwater, …


Biogeochemical Response Of Alpine Lakes To A Recent Increase In Dust Deposition In The Southwestern, Us, Ashley P. Ballantyne, Janice Brahney, C. L. Lawrence, J. Saros, Jason C. Neff Sep 2011

Biogeochemical Response Of Alpine Lakes To A Recent Increase In Dust Deposition In The Southwestern, Us, Ashley P. Ballantyne, Janice Brahney, C. L. Lawrence, J. Saros, Jason C. Neff

Watershed Sciences Faculty Publications

The deposition of dust has recently increased significantly over some regions of the western US. Here we explore how changes in dust deposition have affected the biogeochemistry of two alpine watersheds in Colorado, US. We first reconstruct recent changes in the mass accumulation rate of sediments and then we use isotopic measurements in conjunction with a Bayesian mixing model to infer that approximately 95% of the inorganic fraction of lake sediments is derived from dust. Elemental analyses of modern dust indicate that dust is enriched in Ca, Cr, Cu, Mg, Ni, and in one watershed, Fe and P relative to …


Melt Regimes, Stratigraphy, Flow Dynamics And Glaciochemistry Of Three Glaciers In The Alaska Range, Seth Campbell, Karl Kreutz, Erich Osterberg, Steven Arcone Sep 2011

Melt Regimes, Stratigraphy, Flow Dynamics And Glaciochemistry Of Three Glaciers In The Alaska Range, Seth Campbell, Karl Kreutz, Erich Osterberg, Steven Arcone

Dartmouth Scholarship

We used ground-penetrating radar (GPR), GPS and glaciochemistry to evaluate melt regimes and ice depths, important variables for mass-balance and ice-volume studies, of Upper Yentna Glacier, Upper Kahiltna Glacier and the Mount Hunter ice divide, Alaska. We show the wet, percolation and dry snow zones located below 2700ma.s.l., at 2700 to 3900ma.s.l. and above 3900ma.s.l., respectively. We successfully imaged glacier ice depths upwards of 480m using 40–100MHz GPR frequencies. This depth is nearly double previous depth measurements reached using mid-frequency GPR systems on temperate glaciers. Few Holocene-length climate records are available in Alaska, hence we also assess stratigraphy and flow …


Soil Assessment Of The Weaber Plain (Goomig) Farmlands, Henry Smolinski, Justin Laycock, Jim Dixon Sep 2011

Soil Assessment Of The Weaber Plain (Goomig) Farmlands, Henry Smolinski, Justin Laycock, Jim Dixon

Resource management technical reports

In 2008, the Ord Irrigation Expansion Project was approved by the Western Australian Government to develop irrigated agriculture on the Weaber Plain (Goomig)

As part of the environmental planning and approvals process, the WA Government was required to prepare a groundwater management plan and a hydrodynamic plan.

As a result, the Department of Agriculture and Food, Western Australia (DAFWA) was requested to lead an investigative program to support a second phase of modelling. The project was divided into five components: two addressing deficiencies related to groundwater, two relating to soils and subsoils, and one addressing surface and groundwater quality aspects. …


The Potential For Indicators In The Management Of Climate Change Impacts On Cultural Heritage, Caithleen Daly Sep 2011

The Potential For Indicators In The Management Of Climate Change Impacts On Cultural Heritage, Caithleen Daly

Conference papers

The global scale and unpredictable nature of climate change impacts on cultural heritage poses a challenge for conservation management. This article explores the potential of indicators as an aid for decision makers in the heritage sector. The author proposes a new indicator tool for addressing long-term stone recession impacts that may be related to climate change. The indicator is being installed at two World Heritage sites in Ireland but no results are available. The prototype was developed during doctoral research at the Technological University of Dublin.


Tracking Solutes And Water From Subsurface Drip Irrigation Application Of Coalbed Methane–Produced Waters, Powder River Basin, Wyoming, Mark A. Engle, Carleton R. Bern, Richard W. Healy, James I. Sams, John W. Zupancic, Karl T. Schroeder Sep 2011

Tracking Solutes And Water From Subsurface Drip Irrigation Application Of Coalbed Methane–Produced Waters, Powder River Basin, Wyoming, Mark A. Engle, Carleton R. Bern, Richard W. Healy, James I. Sams, John W. Zupancic, Karl T. Schroeder

United States Geological Survey: Staff Publications

One method to beneficially use water produced from coalbed methane (CBM) extraction is subsurface drip irrigation (SDI) of croplands. In SDI systems, treated CBMwater (injectate) is supplied to the soil at depth, with the purpose of preventing the buildup of detrimental salts near the surface. The technology is expanding within the Powder River Basin, but little research has been published on its environmental impacts. This article reports on initial results from tracking water and solutes from the injected CBM-produced waters at an SDI system in Johnson County, Wyoming.

In the first year of SDI operation, soil moisture significantly increased in …


Stromatolitic Knobs In Storrs Lake, San Salvador, Bahamas: Insights Into Organomineralization, Alexandre J. Fowler Aug 2011

Stromatolitic Knobs In Storrs Lake, San Salvador, Bahamas: Insights Into Organomineralization, Alexandre J. Fowler

Master's Theses

Storrs Lake, a hypersaline lake on the east coast of San Salvador Island, Bahamas, contains well-developed microbial mats, some of which have developed calcified structures called microbialites. Many of these microbialites are laminated, and therefore classified as stromatolites. This study focuses on small stromatolitic knobs located in the southern portion of Storrs lake, which are still actively forming, to gain insights into the early stages of stromatolite formation. These knobs appear to be forming as the result of in situ micritic precipitation mediated by both photosynthetic and heterotrophic microbial metabolisms. By comparing these small stromatolitic knobs to larger stromatolitic heads …


Extreme Variation In The Sagittal Crest Of Tapirus Polkensis (Mammalia Perissodactyla) At The Gray Fossil Site Northeastern Tn., Aaron Randall Abernethy Aug 2011

Extreme Variation In The Sagittal Crest Of Tapirus Polkensis (Mammalia Perissodactyla) At The Gray Fossil Site Northeastern Tn., Aaron Randall Abernethy

Electronic Theses and Dissertations

The preservation and quantity of fossil tapirs (Tapirus polkensis) from the Gray Fossil Site in northeastern Tennessee provides a unique opportunity for comparison and analysis of skeletal characters. Intraspecifically, modern tapirs show little to no variation in the morphology of the sagittal crest. However, several different morphologies exist within the sample at Gray. No osteological evidence of sexual dimorphism exists for tapirs, and no correlation between crest shape and sex was observed. Several juveniles display well defined crests, while some adults have only minor thickening of the temporal ridges; therefore, no distinct correlation between age and crest state …


Biological Effects On Serpentinite Weathering, Mary H. Evert, Julie Baumeister, Elisabeth Hausrath Aug 2011

Biological Effects On Serpentinite Weathering, Mary H. Evert, Julie Baumeister, Elisabeth Hausrath

Undergraduate Research Opportunities Program (UROP)

Serpentinites, perhaps more than any other rock type, control the composition and evolution of the development of the surrounding ecosystems. The bulk chemistry of serpentinite rocks, high in Mg and trace elements, and low in nutrients such as Ca, K, P, and N, causes an extreme and stressful environment for ecosystems. However, the role that those serpentine ecosystems play in development of serpentine soils has not been examined.

Due to the unusual chemistry of serpentine soils, serpentine ecosystems have deeper and better-developed root systems than other ecosystems. The rhizosphere of serpentine systems, documented to produce abundant organic acids and siderophores, …


Designing A Soil Ph Monitoring Network For The Western Australian Wheatbelt, Karen Holmes, Pat Bellamy, Jim Dixon Aug 2011

Designing A Soil Ph Monitoring Network For The Western Australian Wheatbelt, Karen Holmes, Pat Bellamy, Jim Dixon

Resource management technical reports

Natural resource managers in Western Australia require a purposely designed soil pH monitoring network to identify areas at higher risk of soil acidification and to observe changes in soil pH through time. This monitoring network, in conjunction with field experimental work and acidification modelling, will identify state and regional trends and help shape state natural resource management policy and regional extension programmes, as well as directly inform industry and land managers.


Determining The Viability Of A Hybrid Experiential And Distance Learning Educational Model For Water Treatment Plant Operators In Kentucky, Jana R. Fattic Aug 2011

Determining The Viability Of A Hybrid Experiential And Distance Learning Educational Model For Water Treatment Plant Operators In Kentucky, Jana R. Fattic

Masters Theses & Specialist Projects

Drinking water and wastewater industries are facing a nationwide workforce shortfall of qualified treatment plant operators due to factors including the en masse retirement of baby boomers and the tightening of regulatory requirements regarding the hands-on experience required prior to licensure. Rural areas are hardest hit due to the lack of educational and experiential opportunities available to them within a reasonable proximity. Using a variety of demographic and industry data, a geographic analysis of Kentucky was conducted to assess the viability of the traditional classroom delivery model versus a hybrid experiential and distance learning educational model (HEDLEM). Although this analysis …


Assessing Ageing At Beaver Reservoir, Northwest Arkansas: Limnological, Geochemical & Paleolimnological Approach, Byron Anthony Winston Aug 2011

Assessing Ageing At Beaver Reservoir, Northwest Arkansas: Limnological, Geochemical & Paleolimnological Approach, Byron Anthony Winston

Graduate Theses and Dissertations

Access to potable water has been arguably one of the most important requisites for the advancement of human civilization on earth. As a result, man in his infinite wisdom devised the dam and formed reservoirs, (man- made lakes), to exploit water resources at will. In all natural lakes and reservoirs changes occur in the water quality parameters as it relates to chemical nutrients, temperature and turbidity over time. These changes are collectively referred to as "Reservoir Ageing", of which sedimentation and eutrophication are primary. Reservoir Ageing has consequences which adversely affect and defeat many of the intended uses of the …


Geochemical Analysis Of Long Island Sound Sediments, Jaroslaw W. Slusarczyk Aug 2011

Geochemical Analysis Of Long Island Sound Sediments, Jaroslaw W. Slusarczyk

Theses, Dissertations and Culminating Projects

As one of the largest estuarine systems in the northeastern United States, Long Island Sound (LIS) has been exposed to human activities for many centuries. Human settlement and population growth in the last 200 years has caused heavy pollution in LIS through inland and shore industrial and municipal releases. The geochemistry of one sediment core and numerous surface sediment samples were analyzed using environmental forensic techniques. This study employed use of pyrolysis gas chromatography/ mass spectrometry (Py-GC/MS) in conjunction with previously analyzed geochemical and radiometric data to study contamination sources and patterns though LIS. Geochemical analysis of samples was focused …


Quantifying 20th Century Glacier Change In The Sierra Nevada, California, Andrew G. Fountain, Hassan J. Basagic Aug 2011

Quantifying 20th Century Glacier Change In The Sierra Nevada, California, Andrew G. Fountain, Hassan J. Basagic

Geology Faculty Publications and Presentations

Numerous small alpine glaciers occupy the high elevation regions of the central and southern Sierra Nevada, California. An inventory based on 1:24,000 topographic maps revealed 1719 glaciers and perennial snowfields for a total area of 39.15 +/- 0.13 km(2). The number of 'true' glaciers, versus non-moving ice, is estimated to be 122 covering 14.89 +/- 0.08 km(2) or 38% of the ice-covered area. Historic photographs, geologic evidence, and field mapping were used to determine the magnitude of area change over the past century at 14 glaciers. The area change between 1903 and 2004 ranged from -31% to -78%, averaging -55%. …


Changes In Geologic Time Understanding In A Class For Preservice Teachers, Rebecca Teed, William Slattery Aug 2011

Changes In Geologic Time Understanding In A Class For Preservice Teachers, Rebecca Teed, William Slattery

Earth and Environmental Sciences Faculty Publications

The paradigm of geologic time is built on complex concepts, and students master it in multiple steps. Concepts in Geology is an inquiry-based geology class for preservice teachers at Wright State University. The instructors used the Geoscience Concept Inventory (GCI) to determine if students' understanding of key ideas about geologic time and Earth history changed between the first and last day of the course. For three of the four GCI questions analyzed in this study, the number of correct student responses increased significantly between the pretest and the post-test, indicating that many of the students were learning the concepts being …


Groundwater Contamination Potential In Northern Nevada From Mining, Associated Communities, And Agriculture As Forecasted By Two Vulnerability Methods, John L. Swatzell Aug 2011

Groundwater Contamination Potential In Northern Nevada From Mining, Associated Communities, And Agriculture As Forecasted By Two Vulnerability Methods, John L. Swatzell

UNLV Theses, Dissertations, Professional Papers, and Capstones

Two methodologies, DRASTIC and the NDEP method, were used to compare the groundwater vulnerability of mining, associated towns, and agricultural areas in northern Nevada. The DRASTIC and NDEP methods were compared to determine which method produces a more accurate depiction of vulnerability. Vulnerability maps were created using the United States Environmental Protection Agency's (USEPA) DRASTIC and Nevada Department of Environmental Protection (NDEP) methodologies. The DRASTIC map uses seven aspect layers of geologic and hydrologic information with assigned values and weights that are applied to a mathematical equation. The NDEP method uses field data collection for potential contaminant sources and well …


Environmental Magnetism Survey Of A Holocene Sedimentary Record From Barilari Bay, Western Antarctic Peninsula, Carl Joseph Natter Jr. Aug 2011

Environmental Magnetism Survey Of A Holocene Sedimentary Record From Barilari Bay, Western Antarctic Peninsula, Carl Joseph Natter Jr.

Theses, Dissertations and Culminating Projects

Barilari Bay is located on the western side of the Antarctic Peninsula (AP), opposite the former Larsen B Ice Shelf on the eastern Antarctic Peninsula. Barilari Bay was swath mapped during United States Antarctic Program cruise NBP10-01 as part of the Larsen Ice Shelf System, Antarctic (LARISSA) program. The bay consists of a series of five basins with water depths greater than 600 meters, from which a suite of kasten cores and jumbo piston cores was collected. Three cores, JPC-127, its trigger core TC- 127, and JKC 55 were collected from the outer portion of the Bay and recovered an …


Effects Of High-Density, Short-Duration Planned Livestock Grazing On Soil Carbon Sequestration Potentials In A Coastal California Mixed Grassland, Kristina Michelle Wolf, Marc Horney, Brent Hallock, Robert T. Rutherford, Anthony T. O'Geen, Royce Larsen, William Plummer Aug 2011

Effects Of High-Density, Short-Duration Planned Livestock Grazing On Soil Carbon Sequestration Potentials In A Coastal California Mixed Grassland, Kristina Michelle Wolf, Marc Horney, Brent Hallock, Robert T. Rutherford, Anthony T. O'Geen, Royce Larsen, William Plummer

Master's Theses

Planned grazing management in rangelands may improve carbon sequestration potential of soils by increasing plant biomass and the rate of nutrient cycling, which might mitigate global warming. The effects of high-intensity, short-duration planned grazing of sheep on several soil and ecosystem properties were investigated on a mixed grassland in San Luis Obispo, CA. The objectives of this study were to (a) identify soil properties related to soil C sequestration in rangelands; (b) determine if planned grazing improved soil carbon sequestration; (c) quantify changes in identified variables in grazed and rested plots; and (d) analyze any changes in plant species composition …